Various substituted benzimidazoles are known to be useful as herbicides. U.S. Pat. No. 3,325,271 describes the use as herbicides of a broad class of substituted benzimidazoles in which there is at least one substituent on the aromatic ring or at the 1- or 2-position of the molecule. The aromatic substituents may be selected from nitro, halo, lower alkyl, lower alkoxy and halo lower alkyl. U.S. Pat. No. 3,412,101 describes a specific group of 2-trifluoromethyl-5-alkylsulfonylbenzimidazoles which have herbicidal activity. U.S. Pat. No. 3,890,344 describes a class of herbicidal 2-haloalkyl-haloalkylsulfonylbenzimidazoles having no 1-substituent. Other patents relating to benzimidazoles are U.S. Pat. Nos. 3,954,438; 3,901,910; 3,652,580; 3,472,865; 3,480,643; 3,531,495; 3,721,678; 3,821,393 and 3,430,259. Some of the compounds employed in the present herbicidal method are known compounds. See, for example, Bannert et al., Chem. Abstracts, Vol. 78, 99066; Sedova et al., Chem. Abstracts, Vol. 72, 31366; Troitskaya et al., Chem. Abstracts, Vol. 79, 54858 and Yagupol'skii et al., Chem. Abstracts, Vol. 53, 21765-21766.